1. Technical Field
The present invention relates generally to an improved data processing system and in particular to a method and apparatus for performing handwriting recognition. Still more particularly, the present invention provides a method and apparatus for reducing the number of comparisons made with a reference character dictionary when performing handwriting recognition.
2. Description of Related Art
In the field of handwriting recognition, various approaches have been taken by software vendors to provide more accurate recognition of handwriting samples. Written languages that have large character sets, e.g., the Chinese and Korean languages, are particularly problematic for software vendors to develop efficient handwriting recognition algorithms. The Chinese language, for example, includes thousands of characters. Accordingly, a reference character dictionary for performing handwriting recognition of the Chinese language necessarily includes thousands of entries. The data size of the characters maintained in the reference dictionary limits the efficiency for performing handwriting analysis of written Chinese characters.
Handwriting recognition solutions require sampling handwritten character strokes during input of the strokes and comparing the samples with reference characters maintained in a reference character dictionary. For example, many handwriting recognition algorithms require construction of an image, such as a bitmap, of the handwritten character for interrogation of a reference character dictionary. For languages including large character sets, thousands of comparisons may be made to identify a potential match. Such techniques are data-intensive and require large processing capacity to effectively implement a handwriting recognition algorithm.
Many languages have rules that define the order in which character strokes are to be written. For example, well established rules dictate the order in which the strokes of Chinese characters are written.
It is desirable to provide a handwriting recognition technique that exploits stroke order rules for reducing the number of comparisons made with a reference character dictionary when performing handwriting recognition. It would be advantageous to enable a user to indicate a knowledge of the stroke order of a language in which the user supplies handwritten characters for analysis by a handwriting recognition algorithm. It would be further advantageous for the handwriting recognition algorithm to exclude attributes of a reference character stroke from comparison with a handwritten stroke, or parameters derived therefrom, when the handwritten stroke is input in a stroke sequence that does not correspond to the reference character stroke sequence. It would still be further advantageous to enable a user to provide an input that indicates a variable knowledge level of the stroke order and for the handwriting recognition algorithm to reduce the number of comparisons made with entries of the reference character dictionary an amount that is dependent on the user input.